EXTERNAL CHARACTERS AND HABITS 7S face, ears, palms and soles is covered with hair, which varies in length and colour in different animals, and in different parts of the body in each. It is, however, of some light or deep shade of reddish-brown. The colour and arrangement have been described by many authors, besides those'given below in the footnote.* In the young animal the brow is more or less hairy (fig. 14), but the brow and its bounding cheek-pads are hairless in the adult (fig. 15). Keith  points out that the arrangement of the hair is due to the fact that, when the animal lies on its side, as it does in sleep, the hair acts the part of a natural thatch. On the neck and shoulders the hair is directed forwards and upwards towards the head; on the back it is directed downwards; on the pectoral extremity the hairs converge towards the elbow -joint, and those on the abdomen and legs point towards the ground. The hairs on the shoulders and the upper arms are the longest, and those on the brow, axillae and ventral abdominal wall are the shortest. Also the hairs on the extensor aspect of the forearm are longer than those on the flexor surface. When the hairs are examined microscopically it is seen how the cuticular scales have sinuous margins, which are quite unlike those of the other Anthropoids; * The extremities have been described or figured by Abel (224) Alix (301), Barkow (302), Beddard (304), Camper (237')* Fick (247), Fletcher (99), Harwood (251), Hepburn (83), Kollniami (346), Lucae (261), Trinchese (292), and Temminck (289). The hairs have been described by Bolau (233), Chapman (238), Deniker (46), Hartmann (452), Martin (355), "Wallace (293),Wenck-stern (297) and others. Much information on the hairs of anthropological interest is contained in the work of Friedenthal (63A). The pattern of the cutieular scales on the hairs has been described by Duncan.